51166-71-3Relevant articles and documents
INCLUSION, COMPLEXATION AND EFFICIENT ENANTIOMERIC DISCRIMINATION BY REGIOSPECIFIC OVERMETHYLATION OF A DIMETHYL-β-CYCLODEXTRIN
Galons, Herve,Gnaim, Jallal,Rysanek, Nicole,LeBas, Genevieve,Villain, Francoise,Tsoucaris, Georges
, p. 181 - 184 (1993)
An unsymmetrically methylated β-cyclodextrin was prepared and allowed the chiral discrimination of the volatile included compound 1,7-dioxaspiro(5,5)undecane 1.
SYNTHESIS AND PROPERTIES OF A SURFACTANT-CYCLODEXTRIN CONJUGATE.
Menger, F. M.,Williams, D. Y.
, p. 2579 - 2582 (1986)
A surfactant-cyclodextrin conjugate, in which an ion-terminated chain is attached to each of the seven cyclodextrin sugars, has been synthesized and examined by a variety of physical methods.
Cyclodextrin inclusion interferes with trolox oxygen radical scavenging capacity measurement
Sueishi, Yoshimi,Ishikawa, Misa,Hori, Masashi,Inazumi, Naoya
, p. 49 - 55 (2013)
The interference of cyclodextrin solubilization with the measurement of oxygen radical scavenging capacity was investigated. Cyclodextrin (CD) that can solubilize water-insoluble compounds has been used in the oxygen radical scavenging capacity assay called oxygen radical absorbance capacity (ORAC) method. A vitamin E analog, trolox (2-hydroxy-2,5,7,8-tetramethylchroman-2- carboxylic acid) has been employed as a standard compound in ORAC methods and the results were often expressed in the trolox equivalent unit. We found that trolox ORAC values measured with electron spin resonance-based ORAC method, were markedly dependent on the CD concentration, i.e., it decreased by 50% when [CD]/[Trolox]=100 was present. 2D ROESY NMR study of trolox/CD inclusion complex revealed that trolox resided within the CD cavity. The reactive phenoxyl group in trolox is shielded from the attack by the oxygen radical, suggesting that this hindrance was causal for the decrease in ORAC values. by Oldenbourg Wissenschaftsverlag, Mu?nchen.
Formation of linear polymers with pendant vinyl groups via inclusion complex mediated polymerization of divinyl monomers
Satav, Sunita S.,Karmalkar, Rohini N.,Kulkarni, Mohan G.,Mulpuri, Nagaraju,Sastry, G. Narahari
, p. 7752 - 7753 (2006)
Ethylene glycol dimethacrylate (EGDMA) and ethylene glycol methacrylate 4-vinyl benzoate (EGMAVB) were shown to form 1:1 inclusion complexes with cyclodextrin and were characterized by instrumental techniques. Computational analysis showed that the bent conformation of the included divinyl monomer was more stable than its linear conformation. Complexation of the divinyl monomer with the first CD molecule offered substantial stabilization than with the second CD molecule. The vinyl group included in the CD cavity did not participate in polymerization. As a result, solvent soluble, linear polymers with pendant vinyl unsaturation per repeat unit were obtained. This was unequivocally established by the polymerization of a complex comprising CD and EGMAVB. The unreacted vinyl group can be polymerized in the subsequent step to yield cross-linked products. Copyright
Growth, shrinking, and breaking of pluronic micelles in the presence of drugs and/or β-cyclodextrin, a study by small-angle neutron scattering and fluorescence spectroscopy
Valero, Margarita,Dreiss, Cecile A.
experimental part, p. 10561 - 10571 (2011/01/12)
The associative structures between F127 Pluronic micelles and four drugs, namely, lidocaine (LD), pentobarbital sodium salt (PB), sodium naproxen (NP), and sodium salicylate (SAL), were studied by small-angle neutron scattering (SANS). Different outcomes for the micellar aggregates are observed, which are dependent on the chemical nature of the drug and the presence of charge or otherwise: the micelles grow with LD, are hardly modified with PB, and decrease in size with both NP and SAL. The partition coefficient, determined by fluorescence spectroscopy, is directly correlated to the amount of charge, following NP ≈ SAL a slightly deeper localization of LD and more superficial for PB. All drugs can form inclusion complexes with heptakis(2,6-di-O-methyl) β-cyclodextrin (hep2,6 β-CD). Hep2,6 β-CD, as shown in previous studies (Joseph, J.; Dreiss, C. A.; Cosgrove, T. Langmuir, 2008, 24, 10005-10010; Dreiss, C. A.; Nwabunwanne, E.; Liu, R.; Brooks, N. J. Soft Matter, 2009, 5, 1888-1896), is also able to form a complex with F127, resulting in micellar breakup. In the ternary mixtures, a fine balance of forces is involved, which results in drastic micellar changes, as observed from the SANS patterns. Depending on the ratio of drug, polymer, and hep2,6 β-CD and the nature of the interactions (which is directly linked to the drug chemical structure), the presence of drug either hinders micellar breakup by β-CD (at high enough concentration of LD or PB) or leads to micellar growth (NP). These effects are mainly attributed to a preferential drug/β-CD interaction (except for PB), which, at least in the conditions studied here, explains the higher β-CD concentration needed for micellar breakup to occur.
Influence of cyclodextrins on the fluorescence of some short and long chain linked flexible bisbenzenes in aqueous solution
Bortolus, Pietro,Monti, Sandra,Smoluch, Miroslawa,Bouas-Laurent, Henri,Desvergne, Jean-Pierre
, p. 1165 - 1171 (2007/10/03)
The UV absorption, induced circular dichroism (icd) spectra, steady state and time resolved fluorescence emission of the flexible bisbenzenes 1-4 were obtained in aqueous solution and in presence of α-, β-, and γ-cyclodextrin (CD). Bisbenzenes 1 and 2 in an aqueous environment exhibit a dual emission which is differently affected by the CDs. The long-wavelength emission is quenched by α- and β-CD and enhanced by γ-CD. This is due to the formation of inclusion complexes between the CDs and 1 (2) in the ground state, in agreement with the modifications of the UV spectrum and the appearance of icd signals. On the basis of these effects and of the influence of the CDs on the 1 and 2 lifetimes, the dual emission of these bisbenzenes is attributed to a set of different ground-state conformations.
Catenated Cyclodextrins
Armspach, Dominique,Ashton, Peter R.,Ballardini, Roberto,Balzani, Vincenzo,Godi, Anna,et al.
, p. 33 - 55 (2007/10/02)
A novel synthetic approach is described for the construction of catenanes in aqueous solution from a partially methylated cyclodextrin (CD)-namely, heptakis(2,6-di-O-methyl-β-cyclodextrin) (DM-β-CD)- and a range of substrate molecules that contain a hydrophobic central core in the form of a 4,4'-disubstituted biphenyl unit (usually bitolyl) carrying two hydrophilic polyether side chains terminated by primary amine functions.In water, the amphiphilic catenane precursors form 1:1 complexes with β-CD and DM-β-CD and 2:1 (guest:host) complexes with the larger γ-CD.Macrocyclizations of the biphenyl-containing substrates with aromatic diacid chlorides in aqueous solution and in the presence of DM-β-CD under Schotten-Baumann conditions afforded - in low yields - a range of - and catenanes.When a consitutionally asymmetrical diamine was employed as the substrate, orientational isomers of a catenane were obtained.A catenane incorporating a macrocyclic tetralactam was found to exist as a mixture of head-to-head and head-to-tail isomers, which could be separated by high pressure liquid chromatography and identified unambiguously by nuclear magnetic resonance spectroscopy.One of the catenanes afforded good single crystals from which the solid state structure was determined by X-ray crystallography.Other techniques which aided the characterization of these novel compounds included ultraviolet/visible and luminescence spectroscopy, dynamic nuclear magnetic resonance spectroscopy and fast atom bombardment mass spectrometry.Generally speaking, the catenated cyclodextrins are soluble in halogenated and aromatic hydrocarbons as well as in hydroxylic solvents.The existence of these new compounds gives us a unique insight into the nature of the noncovalent bonding interactions that cyclodextrins employ in binding substrate molecules. - Keywords: catenanes * cyclodextrins * macrocycles * orientational isomerism
Solution inbuprofen complexes, compositions and processes for preparing the same
-
, (2008/06/13)
Ibuprofen - cyclodextrin complexes wherein the cyclodextrin is selected from the group consisting of α-cyclodextrin, methylated-β--cyclodextrins and γ-cyclodextrin; processes and compositions also being disclosed.
Spectroscopic Study of Hydrophobic Interaction of Heterocyclic Amine N-Oxides with Cyclodextrins
Uno, Bunji,Kaida, Naoki,Kawakita, Toshio,Kano, Kenji,Kubota, Tanekazu
, p. 3753 - 3759 (2007/10/02)
Electronic spectra of aromatic amine N-oxides show a marked blue shift with the change of solvent polarity from aprotic solvents to protic ones.This is very useful to examine the hydrophobic interaction between the amine N-oxides and cyclodextrins (CyD) in water.Among the various systems studied a typical example is the system of 4-nitroquinoline N-oxide (4NQO) and 2,6-di-O-methyl-β-cyclodextrin in water.A clear red shift of the ultraviolet (UV) spectrum of 4NQO was observed upon inclusion complex formation, indicating directly that the CyD cage environment is much more hydrophobic than in water.Thermodynamic and spectroscopic constants pertinent to those inclusion complex formations were evaluated and the results are discussed in relation to the complex formation mechanisms.
Structural Mapping of an Unsymmetrical Chemically Modified Cyclodextrin by High-field Nuclear Magnetic Resonance Spectroscopy
Spencer, Catriona M.,Stoddart, J. Fraser,Zarzycki, Ryszard
, p. 1323 - 1336 (2007/10/02)
Samples of 2,6-per-O-methyl-β-cyclodextrin (DMβCD), prepared according to literature procedures, have shown to be less then 70percent pure.The major impurity has been identified as the unsymmetrical over-methylated cyclodextrin derivative (DM + 1)βCD.Samples of pure DMβCD and (DM + 1)βCD have been prepared by (i) benzoylating a chromatographically homogeneous mxture obtained after methylating βCD with dimethyl sulphate, (ii) separating chromatographically the resulting DMβCD heptabenzoate (DMβCD-B7) and (DM + 1)βCD hexabenzoate 6>, and then (iii) subjecting the pure perbenzoates to de-O-benzoylation.Both DMβCD-B7 and (DM + 1)βCD-B6 have been fully characterised.High-resolution 1H and 13C n.m.r. spectroscopy, COSY, J-resolved, JMOD, XHCORRD, and CHORTLE) for signal assignment and n.O.e. difference spectroscopy for residue sequencing, has been used to assign individually (i) 41 out of the 49 heterotropic protons and (ii) 29 out of the 42 heterotropic carbon atoms of the unsymmetrical (DM + 1)βCD-B6 (nuclei associated with O-methyl and O-benzoyl groups were excluded from consideration).The complete spectroscopic characterisation of unsymmetrical chemically modified cyclodextrins is important in the investigation of these compounds as potential enzyme models.The necessity of preparing pure chemically modified cyclodextrin derivatives cannot be over-emphasised.
